Saturnus, Aedes (Fig. 19): a temple about which there was much disagreement. Macrobius (Macrobius Sat. 1.8.1) knew a tradition that ascribed a fanum Saturni and the establishment of the Saturnalia to Tullus Hostilius, but also knew that Varro thought that L. Tarquinius (Priscus?) had let the contract for the temple building and that Titus Larcius dedicated it as dictator, an office he may have held in connection with one of his consulships in 501 and 498, or shortly thereafter. This was the commonest belief (see Dion. Hal. 6.1.4). But there were those who assigned its dedication to other magistrates of the first years of the republic, Aulus Sempronius Atratinus and M. Minucius Mamercus, the consuls of 497 (Livy 2.21.1-2; Dion. Hal. 6.1.4), Postumus Cominius, consul in 501 and 493 (Dion. Hal. 6.1.4), the last tradition ascribed to a Gellius, probably Cn. Gellius, the annalist of the second century B.C. Almost everyone agrees that the temple belongs to the beginning of the republic and that it was the oldest temple whose building was recorded in the records of the pontifices. Its location was variously given as in faucibus (Montis Capitolini) (Varro Ling. 5.42), sub Clivo Capitolino (Servius ad Aen. 8.319; Aur. Vict. Orig. Gent. Rom. 3.6), ante Clivum Capitolinum (Servius ad Aen. 2.116; Hyginus Fab. 261), ad forum (Macrobius Sat. 1.8.1), and in Foro Romano (Livy 41.21.12).

In 174 B.C. a portico was built from the temple to the Senaculum, ac super id Curiam. This must have run along the shoulder of the Capitoline, but how it can have reached the Curia without passing through the Comitium is a hard question. The answer may be that a columnar porch similar to that of the Curia Iulia (q.v.) was added to the façade of the Curia Hostilia either at this time or earlier, and the new portico adjoined it at one end. The fact that such a porch was a feature of the third-century curia of Paestum may strengthen the argument. In any case, this portico must have been a relatively light structure that has disappeared without leaving any trace. In 42 B.C. L. Munatius Plancus rebuilt the temple (Suetonius Aug. 29.5; CIL 6.1316 = ILS 41, CIL 10.6087 = ILS 886). It is mentioned casually in connection with the arch of Tiberius of A.D. 16 (Tacitus Ann. 2.41). It burned sometime in the later fourth century and was then restored by vote of the senate, as is recorded on the architrave (CIL 6.93 =.ILS 3326). It is listed in the regionary catalogues in Regio VIII.

Throughout the republic, this temple contained the state treasury, the Aerarium Populi Romani, or Aerarium Saturni (Paulus ex Fest. 2L; Solinus 1.12; Macrobius Sat. 1.8.3), administered by quaestors, for whom it became a sort of headquarters (Plutarch Ti. Gracch. 10.6; Appian BellCiv 1.31). In the temple was kept a pair of scales in memory of a time when payment had been by weight (Varro Ling. 5.183). Under the empire the Aerarium Populi Romani was distinguished from the fiscus, the privy purse of the emperor, and continued to reside in the temple, but seems now to have been administered by praefecti (Pliny Epist. 10.3.1). For inscriptions mentioning the aerarium, see DE 1.300; for occurrences of the phrase Aerarium Populi Romani and Aerarium Saturni, see TLL 1.1055-58. Other public documents were affixed in numbers to the exterior (Varro Ling. 5.42; Cass. Dio 45.17.3), perhaps because of the temple's association with the quaestors.

On the gable of the temple were acroteria of Tritons blowing trumpets (Macrobius Sat. 1.8.4), and in the cella was a statue, probably with substantial parts of ivory, for it was filled with oil (Pliny HN 15.32), whose feet were shackled with woolen bonds except on the Saturnalia (Macrobius Sat. 1.8.5). It seems doubtful that this was the image carried in solemn processions and lectisternia (Dion. Hal. 7.72.13). The day of dedication was the Saturnalia, 17 December (Fast. Amit. ad. XVI Kal. Ian.; Degrassi 538-40).

A very small part of the temple was shown on one fragment of the Marble Plan, now lost (FUR pl. 13.24 = 21.18d; Rodriguez pl. 13.18d), and another, also lost, has erroneously been thought to show the stair of approach (FUR pl. 3.3 = 21.19; Rodriguez pl. 13.19) but can be demonstrated not to belong to the temple at all.

A few blocks of the original structure survive, but most of what can be seen of the podium today belongs to the reconstruction of Plancus, a mass of concrete faced with walls of blocks of travertine and peperino that were revetted with marble. It is 22.50 m wide and about 40 m long; the back is at present in the process of being excavated for the first time. There is no evidence of any building period intermediate between the original construction and Plancus's reconstruction, unless Gellius's record of a dedication by the tribunus militum L. Furius of a building dcreed by the senate (Macrobius Sat. 1.8.1) refers to a rebuilding of the late fifth or fourth century B.C. In that case it might refer to a rebuilding after the fire of the Gauls.

The temple stands very high on its podium because of its situation on the slope of the Capitoline. The superstructure is that of the rebuilding after the fire in the fourth century. The columns are of granite, six on the façade of gray granite, the pairs behind them on either side of the pronaos of rose granite. The bases are of white marble and of three types, and the capitals are four-sided Ionic of very late type, almost proto-Byzantine. The entablature blocks are reused with sketchy patching of lacunas, of Proconnesian marble, perhaps of Severan date, whereas the cornice is considered Augustan, possibly part of Plancus's building but clumsily reassembled. The columns are 11 m high, but of unpleasing effect. The whole points to a reconstruction when the classical tradition of working stone had been lost, but a new aesthetic had not yet taken its place.

The steps of the temple have disappeared, but the Aerarium must have been arranged under them. In Pompeii the aerarium was in vaulted chambers under the Capitolium (Temple of Jupiter) at the end of the forum, accessible from a platform at midstair in the stair of approach across the façade. Here the stair divided into three parts, those on either side continuing up to the pronaos, and that in the middle descending to the aerarium (A. Maiuri, Alla ricerca di Pompei preromana [Naples 1973], 104-6). A similar arrangement in Rome would suit the information that during Milo's trial Pompey set his curule chair pro aerario (Asconius in Cic. Milon. Arg. 36 [Stangl 36]). That there was a single door to the Aerarium seems shown by Tiberius Gracchus's sealing of this with his personal seal in 133 B.C. (Plutarch Ti. Gracch. 10.6). The temple was well preserved until the fifteenth century, according to Poggio, and destroyed between 1402 and 1447 (VZ 4.235).

Lugli 1946, 149-51; Collection Latomus 58 (1962): 757-62 (E. Gjerstad); AJA 84 (1980): 51-62 (L. Richardson); R. Pensabene, Tempio di Saturno, architettura e decorazione (Rome 1984).